Light-stabilized ink composition

ABSTRACT

2-(2&#39;-Hydroxyphenyl)benzotriazoles of formula I ##STR1## wherein R 1 , R 2  and R 3  are as defined in claim 1, and which contain at least one --SO 3  X group in the molecule, are suitable light stabilizing additives for aqueous ink compositions, especially for ink jet printing. Some of these compounds are novel compounds.

This application is a division of application Ser. No. 569,321, filedAug. 17, 1990, now abandoned.

The present invention relates to aqueous ink compositions which containa water-soluble derivative of a 2-(2'-hydroxyphenyl)benzotriazole. Theseink compositions are particularly suitable for ink jet printing. Theinvention further relates to novel sulfonated2-(2'-hydroxyphenyl)benzotriazoles.

Printing by ink jet printing is a very rapid printing method which iscontrolled by electrical signals. This method comprises jetting fine inkdroplets through an orifice on to the recording material. The ink usedis preferably an aqueous solution of a water-soluble dye. The dye willnormally have a lower lightfastness than the dyestuff pigments used inconventional printing methods. The consequence is that the printsobtained have only a limited storage life when exposed to light.

The proposal has therefore already been made (U.S. Pat. No. 4,256,493)to add a water-soluble UV absorber of the sulfonated hydroxybenzophenonetype to the ink. The metal salts of such compounds have also beenproposed as light stabilising additives for ink jet printing inks (JPA-46277/88).

The drawback of such benzophenone derivatives and their salts is thatthey cause discolourations when added to specific dyes, especially blackdyes.

Carboxylic acid derivatives of UV absorbers of the benzotriazole typehave also been proposed in Research Disclosure 22 519 for stabilisingdyes and inks. However, these derivatives are not sufficiently solublein aqueous systems.

It has now been found that specific water-soluble derivatives of2-(2'-hydroxyphenyl)benzotriazoles are readily suitable lightstabilising additives for aqueous ink compositions, especially for inkjet printing.

Specifically, the invention relates to aqueous ink compositions whichcontain, as light stabiliser, at least one compound of formula I##STR2## wherein R₁ is hydrogen, halogen, C₁ -C₄ alkyl, C₁ -C₄ alkoxy,--COO--R₉ --OSO₃ X, --COOX or --SO₃ X,

R₂ is hydrogen, OH, C₁ -C₈ alkyl, C₅ -C₆ cycloalkyl, phenyl, naphthyl,C₇ -C₁₂ aralkyl, halogen, C₁ -C₈ alkoxy or a --Y--Z group,

R₃ is hydrogen, C₁ -C₈ alkyl, a --Y--Z group or a --Y--O--Z' group,

X is hydrogen or M,

M is Li, Na, K, 1/2 Mg, 1/2 Ca, 1/2 Zn, 1/2 Co (II), 1/2 Cu (II), 1/2 Ni(II), 1/3 Cr (III), 1/3 Fe (III), ##STR3## wherein R₄, R₅, R₆ and R₇ areeach independently of one another hydrogen, C₁ -C₁₂ alkyl, hydroxyethyl,cyclohexyl, phenyl or benzyl,

Y is a direct bond or a divalent group of one of the following formulae:##STR4## wherein R₈, R₉, R₁₀ and R₁₁ are each independently of oneanother C₁ -C₂₀ alkylene which may be substituted by 1-10 hydroxylgroups or are C₂ -C₂₀ alkylene which is interrupted by 1-10 --O-- or--NH--, and

Z is a --COOX or --SO₃ X group, and Z' is --SO₃ X,

with the proviso that the compound of formula I contains at least onegroup of formula --COOX or --SO₃ X.

R₁ as C₁ -C₄ alkyl may be methyl, ethyl, propyl, isopropyl, n-butyl,sec-butyl, isobutyl or tert-butyl. R₂ and R₃ as C₁ -C₈ alkyl may furtherbe n-pentyl, sec-pentyl, tert-pentyl, n-hexyl, isohexyl, 2-ethylbutyl,n-heptyl, isoheptyl, n-octyl, 2-ethylhexyl or tert-octyl. R₄ -R₇ as C₁-C₁₂ alkyl may additionally be n-decyl, n-dodecyl or isononyl.

R₂ as cycloalkyl or aryl may be cyclopentyl, cyclohexyl, phenyl ornaphthyl. R₂ as aralkyl may be benzyl, α-methylbenzyl,α,α-dimethylbenzyl or naphthylmethyl.

R₁ as C₁ -C₄ alkoxy may be methoxy, ethoxy, isopropoxy or butoxy. R₂ asC₁ -C₈ alkoxy may be additionally be pentyloxy, hexyloxy, heptyloxy oroctyloxy.

R₈ as C₁ -C₈ alkylene may be unbranched or branched alkylene, such asmethylene, di-, tri-, tetra-, penta-, hexa- and octamethylene,1,2-propylene or 2-methyltetramethylene. R₉, R₁₀ and R₁₁ as C₁ -C₂₀alkylene may additionally be octa-, deca-, dodeca-, hexadeca- oroctadecamethylene. Preferably R₈, R₉, R₁₀ and R₁₁ are C₁ -C₄ alkylene.

R₈, R₉, R₁₀ and R₁₁ as alkylene which is interrupted by --O-- may be3-oxatetramethylene, 3,6-dioxaoctamethylene,3,6,9,12-tetraoxatetradecamethylene or radicals of formulae --OC₂ H₄)₂und --OC₂ H₄)₆. R₉, R₁₀ and R₁₁ as OH-substituted alkylene may be inparticular 2-hydroxytrimethylene.

The ink compositions preferably contain, as light stabiliser, a compoundof formula I, wherein

R₁ is hydrogen, halogen, C₁ -C₄ alkyl, C₁ -C₄ alkoxy, --COO--R₉ --OSO₃X, --COOX or --SO₃ X,

R₂ is hydrogen, C₁ -C₈ alkyl, C₇ -C₉ phenylalkyl or a --Y--Z group,

R₃ is hydrogen, C₁ -C₄ alkyl, --Y--Z group or a --Y--O--Z' group,

X is hydrogen or M,

M is Li, Na, K, ##STR5## wherein R₄, R₅, R₆ and R₇ are eachindependently of one another H, C₁ -C₄ alkyl or hydroxyethyl,

Y is a direct bond or a group selected from ##STR6## wherein R₈ is C₁-C₆ alkylene and R₉ and R₁₀ are each independently of the other C₁ -C₁₀alkylene which may be substituted by 1 or 2 hydroxyl groups or C₂ -C₂₀alkylene which is interrupted by 1-10 --O--, and

Z is a --COOX or --SO₃ X group and is Z' --SO₃ X, especially thosecompounds of formula I,

wherein R₁ is hydrogen, chloro, --CO--OC₂ H₄)_(x) OSO₃ X, --COOX or--SO₃ X,

R₂ is hydrogen, C₁ -C₈ alkyl, C₇ -C₉ phenylalkyl or a --Y--Z group,

R₃ is hydrogen or a --Y--Z group and x is an integer from 2 to 8.

Particularly preferred ink compositions are those containing a compoundof formula I, wherein

R₁ is hydrogen, chloro, --CO--OC₂ H₄)_(x) OSO₃ X, --COOX or --SO₃ X,

R₂ is hydrogen, C₁ -C₈ alkyl, C₇ -C₉ phenylalkyl or a --Y--Z group,

R₃ is hydrogen or a --Y--Z group, x is an integer from 2 to 8,

X is Li, Na, K or ##STR7## Y is a direct bond or a group selected from--R₈ --, --R₈ --CONH--R₉ --, ##STR8## or --R₈ --COO--R₉ --, Z is a--COOX or --SO₃ X group,

R₄, R₅, R₆ and R₇ are each independently of one another C₁ -C₄ alkyl orhydroxyethyl,

R₈ is C₁ -C₆ alkylene and R₉ is C₁ -C₁₀ alkylene which may besubstituted by 1 or 2 hydroxyl groups or is C₂ -C₂₀ alkylene which isinterrupted by 1-10 --O.

X is preferably Li, Na, K, NH₄ or tetraalkylammonium and is mostpreferably lithium.

The compounds of formula I preferably contain two --COOX or --SO₃ Xgroups, most preferably two --SO₃ X groups.

R₂ is preferably in ortho-position and R₃ is preferably in para-positionto the hydroxyl group of the hydroxylphenyl radical in formula I.

Illustrative of individual compounds of formula I are: ##STR9##

The eligible compounds of the invention contain at least one carboxylicacid or sulfonic acid group or salts thereof. Compounds containing twocarboxylic acid groups are already known (GB patent 981 539, Frenchpatent 1 370 874). The other compounds are novel compounds and likewiseconstitute an object of the invention.

Accordingly, the invention also relates to compounds of formula I'##STR10## wherein R₁ is hydrogen, halogen, C₁ -C₄ alkyl, C₁ -C₄ alkoxy,--COO--R₉ --OSO₃ X, --COOM or --SO₃ X,

R₂ is hydrogen, OH, C₁ -C₈ alkyl, C₅ -C₆ cycloalkyl, phenyl, naphthyl,C₇ -C₁₂ aralkyl, halogen, C₁ -C₈ alkoxy or a --Y--Z group,

R₃ is hydrogen, C₁ -C₈ alkyl or a --Y--Z group, X is hydrogen or M,

M is Li, Na, K, 1/2 Mg, 1/2 Ca, 1/2 Zn, 1/2 Co (II), 1/2 Cu (II), 1/2 Ni(II), 1/3 Cr (III), 1/3 Fe (III), ##STR11## wherein R₄, R₅, R₆ and R₇are each independently of one another hydrogen, C₁ -C₁₂ alkyl,hydroxyethyl, cyclohexyl, phenyl or benzyl,

X is hydrogen or M,

Y is a group selected from --R₈ --, --R₈ --CONH--R₉ --, ##STR12## --R₈--COO--R₉ --, --R₈ --SO₂ --R₉ --, --R₈ --SO₂ NH--R₉ --, ##STR13##wherein R₈, R₉, R₁₀ and R₁₁ are each independently one another C₁ -C₂₀alkylene which may be substituted by 1-10 hydroxyl groups or C₂ -C₂₀alkylene which is interrupted by 1-10 --O-- or --NH--,

and Z is a --COOM or --SO₃ X group, with the proviso that the compoundof formula I' contains at least one --COOX group and/or at least one--SO₃ X group.

These compounds can be prepared by methods analogous to those forpreparing other 2-(2-hydroxyphenyl)benzotriazoles from the diazoniumsalts of the corresponding o-nitroanilines by coupling to thecorresponding substituted phenols and reduction of the resultant azocompound by cyclisation according to the scheme: ##STR14##

Alternatively, a sulfonic acid radical R₁, R₂ or R₃ can also beintroduced by sulfonating the corresponding benzotriazole. Thesulfonation can be carried out by the conventional methods ofsulfonating aromatic compounds, for example with chlorosulfonic acid. Afurther alternative method of introducing a sulfonic acid group is theexchange of a tertiary alky group R₂ or R₃ by a SO₃ H group by heatingin concentrated sulfuric acid.

In these syntheses, the products are normally obtained as the freecarboxylic or sulfonic acids, from which the corresponding salts can beprepared by neutralisation with a suitable base, for example byneutralisation with a hydroxide, oxide or carbonate, ammonia or anorganic amine.

Those compounds of formula I which contain two --SO₃ X groups arepreferred.

Also preferred are compounds of formula I', wherein R₁ is hydrogen, Cl,--CO--OC₂ H₄)_(x) OSO₃ X, --COOX or --SO₃ X,

R₂ is hydrogen, C₁ -C₈ alkyl, C₇ -C₉ phenylalkyl or a --Y--Z group,

R₃ is hydrogen or a --Y--Z group,

X is Li, Na, K or ##STR15## x is an integer from 2 to 8, Y is a --R₈ --or --R₈ --COO--R₉ --group, wherein R₈ and R₉ are C₁ -C₄ alkylene, and Zis a --COOX or --SO₃ X group, with the proviso that the compounds offormula I' contain at least two --SO₃ X groups.

In preferred compounds of formula I', the substituent R₂ is inortho-position and the substituent R₃ is in para-position to thehydroxyl group of the hydroxyphenyl radical.

The compounds of formula I are preferably added to the ink compositionsin an amount of 0.01 to 20% by weight, preferably of 0.1 to 10 % byweight. They are readily soluble in these concentrations.

The ink compositions are aqueous compositions. They contain at least 30%by weight of water. In addition to water, they may contain (up to 70% byweight) one or more water-miscible solvents such as ethylene glycol, di-or triethylene glycol, propylene glycol or ethers of such glycols,1,4-butanediol, thiodiglycol, glycerol and the ethers thereof,polyglycerol, mono-, di- and triethanolamine, propanolamine, dimethylformamide, dimethyl sulfoxide, dimethyl acetamide, N-methylpyrrolidone,methanol, ethanol, isopropanol, n-propanol, diacetone alcohol, acetone,methyl ethyl ketone or propylene carbonate.

The ink compositions preferably contain 50% by weight of water.

The ink compositions contain water-soluble dyes or mixtures of the dyesknown for colouring natural fibres. These dyes may be typically mono-,di- or polyazo dyes, triphenylmethane dyes, reactive dyes orphthalocyanine dyes. Examples of such dyes are the dyes Acid Red 14,Acid Red 52, Reactive Red 40, Acid Yellow 17, Acid Yellow 23, DirectYellow 86, Acid Red 35, Acid Red 249, Direct Red 227, Acid Blue 9,Direct Blue 86, Direct Blue 199, Food Black 2, Direct Black 19, DirectBlack 38, Direct Black 168 and Sulphur Black 1 listed in the ColourIndex. The ink compositions will normally contain 0.5-6% by weight ofdye.

The ink compositions may also contain minor amounts of various modifierssuch as binders, surfactants, biocides, corrosion inhibitors,sequestrants, pH buffers or conductivity additives. They may alsocontain further water-soluble light stabilisers. Normally, however, theaddition of one or more stabilisers of formula I to the ink compositionwill suffice in the practice of this invention.

The stabilised ink compositions of this invention are preferably usedfor ink jet printing.

They can, however, also be used for all other conventional utilities forinks, for example for felt-tipped pens, ink pads, fountain pens, penplotters, typewriter ribbons or as printing inks for different printingtechniques.

Different techniques are used in ink jet printing, depending on theapparatus employed. Thus, for example, there are drop-on-demandprinters, bubble-jet printers, continuous-jet printers or compound-jetprinters. The stabilised ink compositions of this invention can be usedfor all these techniques.

The effect of the addition of a compound of formula I to the inkcompositions consists in the enhanced light stability of the printedimage produced with the composition. The effect can be measuredexperimentally by rapid exposure of specimen prints in an exposureapparatus, as shown in the Examples herein. Parts and percentages inthese Examples are by weight.

The recording materials of this invention, which are preferably used forink jet printing, consist of a substrate having a surface which isprintable by means of an ink jet. The substrate is normally paper or aplastic sheet and is usually coated on one side with a material which iscapable of absorbing ink. This layer will preferably contain SiO₂ andpolyvinyl alcohol.

Uncoated paper can also be used. In this case, the paper actssimultaneously as substrate and ink absorbing layer. Materials made ofcellulosic fibres and textile fibre materials such as cotton fabric orblends of cotton and polyacrylamide or polyester, which materialscontain compounds of formula I, can also be used for ink jet printing.

The recording materials can also be tranparent, as in the case ofprojection transparencies.

Alternatively, the compounds of formula I can also be incorporated intorecording materials, particularly those suitable for ink-jet printing.

In the first method, the compounds of the formula I can be addeddirectly to the pulp in the paper manufacture.

A second method of application is spraying the substrate with a solutionof compounds of formula I. The solution is in this case an aqueoussolution or a solution in a slightly volatile organic solvent. Sprayingor impregnating the material with an organic solution of a compound offormula I is especially suitable when using oil-soluble compounds offormula I. The use of emulsions or dispersions is also possible.

Normally, however, a coating composition having affinity for dyes isapplied to the substrate and the compounds of formula I are added tothis composition. The coating compositions normally consist of a solidfiller, a binder and conventional additives.

The filler constitutes the bulk of the coating composition. Examples ofsuitable fillers are SiO₂, kaolin, talcum, calcium, magnesium oraluminium silcates, gypsum, zeolith, bentonite, diatomaceous earth,vermiculite, starch or the surface-modified SiO₂ described in JP-A60-260 377. Minor amounts of white pigments such as titanium dioxide,barytes, magnesium oxide, lime, chalk or magnesium carbonate can be usedwith the filler in the coating composition, provided they do notdrastically lower the density of the ink jet print.

Coating compositions suitable for transparent projectable recordingmaterials may not contain any light-scattering particles such aspigments and fillers.

The binder binds the fillers to one another and to the substrate.Typical conventional binders are water-soluble polymers such aspolyvinyl alcohol, partially hydrolysed polyvinyl acetate, celluloseethers, polyvinyl pyrrolidone and copolymers thereof, polyethyleneoxide, salts of polyacrylic acid, sodium alginate, oxidised starch,gelatin, casein, vegetable gum, dextrin, albumin, dispersions andpolyacrylates or acrylate/methacrylate copolymers, lattices of naturalor synthetic rubber, poly(meth)acrylamide, polyvinyl ethers, polyvinylesters, copolymers of maleic acid, melamine resins, urea resins or thechemically modified polyvinyl alcohols disclosed in JP-A 61-134 290 orJP-A 61-134 291.

An additional dye receptor or a mordant which enhances the fixation ofthe dye to the coating may be added to the binder. Dye receptors foracid dyes are cationic or amphoteric. Exemplary of cationic receptorsare polymeric ammonium compounds such aspolyvinylbenzyltrimethylammonium chloride, polydiallyldimethylammoniumchloride, polymethacryloxyethyldimethylhydroxyethylammonium chloride,polyvinylbenzylmethylimidazolium chloride, polyvinylbenzylpicoliniumchloride or polyvinylbenzyltributylammonium chloride. Further examplesare basic polymers such as poly(dimethylaminoethyl)methacrylate,polyalkylenepolyamines and their condensation products withdicyandiamide, amine/epichlorohydrin polycondensates or the compoundsdisclosed in JP-A-57-36 692, 57-64 591, 57-187 289, 57-191 084, 58-177390, 58-208 357, 59-20 696, 59-33 176, 59-96 987, 59-198 188, 60-49 990,60-71 796, 60-72 785, 60-161 188, 60-187 582, 60-189 481, 60-189 482,61-14 979, 61-43 593, 61-57 379, 61-57 380, 61-58 788, 61-61 887, 61-63477, 61-72 581, 61-95 977, 61-134 291 or in U.S. Pat. Nos. 4,547,405 and4,554,181 as well as in DE-A-3 417 582. An amphoteric dye receptor is,for example, gelatin.

The coating having affinity for dyes may contain a number of otheradditives such as antioxidants, further light stabilisers (alsoincluding UV absorbers which do not conform to the light stabilisers ofthis invention), viscosity improvers, fluorescent whitening agents,biocides and/or antistatic agents.

Representative examples of particularly suitable antioxidants aresterically hindered phenols and hydroquinones, for example theantioxidants disclosed in GB-A 2 088 777 or JP-A-60-72 785, 60-72 786and 60-71 796.

Representative examples of particularly suitable light stabilisers areorganic nickel compounds and sterically hindered amines, for example thelight stabilisers disclosed in JP-A-58-152 072, 61-146 591, 61-163 886,60-72 785 and 61-146 591 or in GB-A-2 088 777, JP 59-169 883 and 61-177279.

Suitable UV absorbers which may be added to a coating composition inconjunction with compounds of formula I are disclosed, for example, inResearch Disclosure No. 24 239 (1984) page 284, GB-A-2 088 777 andEP-A-0 280 650. Suitable UV absorbers for concurrent use with compoundsof formula I in recording substrates for ink jet printing are inparticular those of the 2-hydroxyphenylbenzotriazole class and, mostparticularly, 2-(2'-hydroxy-3',5'-di-t-amylphenyl)benzotriazole and2-(2'-hydroxy-3'-t-butyl-5'-polyglycolpropionate-phenyl)benzotriazole.The UV absorbers can be added to the coating composition as emulsion ordispersion. If the compound of formula I is an acid, it can be dissolvedin the coating composition by addition of alkali. Compounds of formula Iwhich are not acids can be dissolved either direct in the coatingcomposition or are added to it in the form of an emulsion or suspension.

The coating composition is normally applied to the substrate, forexample paper, and dried by heating. As already mentioned, the compoundsof formula I can be also applied to the recording substrate in aseparate operation, alone or together with other already describedcomponents, as aqueous solution. Application can be made by spraying, bysizing in a sizing press, by a separate coating operation or byimmersion in a vat. After subjecting the recording substrate to such anaftertreatment, an additional drying step is necessary.

The recording substrate preferably contains 1 to 10,000 mg/m², mostpreferably 50 bis 2000 mg², of at least one compound of formula I.

EXAMPLE 1

A coating composition based on silica/polyvinyl alcohol is prepared fromthe following components:

16.34 g of a 10% solution of polyvinyl alcohol (Riedel de Haen GmbH)

0.02 g of di-tert-octylphenylpolyethylene oxide

2.00 g of silica (Type 244, W.R. Grace and Co.)

9.54 g of water.

The resultant coating composition is dispersed by ultrasonication andfiltered through a sieve of polyester fibres having a mesh size of 24μm. The pH is adjusted to 7.0 by addition of 2N sodium hydroxidesolution.

The coating composition is applied with a wire applicator tophotographic paper in a thickness of 36 μm. After drying with warm air,the coating has a dry weight of ca. 5.0 g/m².

The recording material is printed with an ink composition of thisinvention which contains a UV absorber of formula I and a comparison inkcomposition which does not contain a UV absorber.

The ink is prepared as follows:

3 g of a UV absorber of formula ##STR16## are dissolved in a mixture of83 g of water and 15 g of glycerol. A dye solution is prepared from 4 gof C.I. Food Black 2 in 80 g of water and 15 g of glycerol. Bothsolutions are filtered through a membrane filter with a pore size of 0.3μm, and combined. The printing ink composition so obtained consists of:

81.5% of water

15% of glycerol

2% of dye

1.5% of UV absorber.

The blank specimen is prepared by combining the dye solution with equalparts of a mixture of 86 g of water and 15 g of glycerol.

The inks are filled into ink cartidges of a Hewlett-Packard "Think-Jet"ink jet printer. Specimen prints having a density of 192×96 dots perinch (75.6×37.8 dots per cm²) are prepared.

After storage for 1 week to dry out the print completely, the colourdensity of the specimen prints is measured with a Macbeth TR 924densitometer using a status A filter. The specimen prints are thenirradiated in an Atlas Weather-O-Meter with a xenon lamp having anintensity of 81 klux behind a filter of 6 mm thick window glass. Thecolour intensity is measured once more to ascertain the percentage lossof intensity.

The results are reported in the following table. Lower values denotehigher lightfastness.

    ______________________________________                                        UV absorber                                                                              Loss of colour density after exposure                              ______________________________________                                        none       15%                                                                1.5%       10%                                                                ______________________________________                                    

The same test is made using sodium2-hydroxy-4-methoxybenzophenone-5-sulfonate as UV absorber. Adiscolouration of the black print to brownish black occurs.

EXAMPLE 2

An ink concentrate consisting of 4 g of C.I. Acid Red, 25 g ofdiethylene glycol and 70 g of water, and a UV absorber concentrateconsisting of 4 g of UV absorber, 25 g of diethylene glycol and 70 g ofwater, are prepared. The following compounds are used as UV absorbers:##STR17## and, as comparision UV absorbers, the compounds of formulae##STR18##

Ink compositions are prepared from 1 part of dye concentrate and UVabsorber concentrate and filled into cartridges of a Hewlett PackardQuiet Jet printer. After preparing specimen prints on paper suitable forink jet printing, the lightfastness of these prints is tested asdescribed in Example 1. The results are reported in Table 1.

                  TABLE 1                                                         ______________________________________                                                      Loss of density                                                 UV absorber   (15 kJ/cm.sup.2)                                                ______________________________________                                        without       63%                                                             UV II         50%                                                             UV III        46%                                                             V I           59%                                                             V II          69%                                                             ______________________________________                                    

EXAMPLE 3

As described in Example 2, ink compositions are prepared from the dyesFood Black 2, Acid Red 14,27,35 and 249, Direct Red 227 and Reactive Red24, while the UV absorber concentrate consists of 6 g of UV absorber, 25g of diethylene glycol and 70 g of water.

Prior to use, the concentrate containing Reactive Red is adjusted withlithium hydroxide to pH 12.0, heated for 30 minutes at 95°-100° C., andsubsequently adjusted with sulfuric acid to pH 7.

The prints are prepared and the lightfastness test is carried out asdescribed in Example 2. The results are reported in Table 2.

                                      TABLE 2                                     __________________________________________________________________________           Loss of colour density in % after exposure to light energy of 15              kJ/cm.sup.2                                                            UV Absorber                                                                          Food Black 2                                                                          Acid Red 249                                                                          Direct Red 227                                                                        Acid Red 14                                                                           Acid Red 35                                                                           Reactive Red                                                                           Acid Red              __________________________________________________________________________                                                            27                    without                                                                              53      63      72      90      75      54       81                    UV I   35      45      57      78      65      37       63                    V I    47      55      78      85      80      57       78                    V II   57      78      72      91      92      66       88                    __________________________________________________________________________     UV I corresponds to the compound of formula                                   ##STR19##                                                                

What is claimed is:
 1. A method of stabilizing an ink jet print againstthe deleterious effects of light which comprisespreparing an aqueoussolution containing at least 30% by weight of water and(i) an effectivecoloring amount of a water soluble dye, and (ii) 0.01 to 20% by weight,based on the total solution, an effective stabilizing amount, of atleast one compound of formula I ##STR20## wherein R₁ is hydrogen,halogen, C₁ -C₄ alkyl, C₁ -C₄ alkoxy, --COO--R₉ --OSO₃ X, --COOX or--SO₃ X R₂ is hydrogen, OH, C₁ -C₈ alkyl, C₅ -C₆ cycloalkyl, phenyl,naphthyl, C₇ -C₁₂ aralkyl, halogen, C₁ -C₈ alkoxy or a --Y--Z group, R₃is hydrogen, C₁ -C₈ alkyl, a --Y--Z group or a --Y--O--Z' group, X ishydrogen or M, M is Li, Na, K, 1/2 Mg, 1/2 Ca, 1/2 Zn, 1/2 Co (II), 1/2Ni (II), 1/3 Cr (III), 1/3 Fe (III), ##STR21## wherein R₄, R₅, R₆ and R₇are each independently of one another hydrogen, C₁ -C₁₂ alkyl,hydroxyethyl, cyclohexyl, phenyl or benzyl, Y is a direct bond or adivalent group of one of the following formulae: ##STR22## wherein R₈,R₉, R₁₀ and R₁₁ are each independently of one another C₁ -C₂₀ alkylenewhich may be substituted by 1-10 hydroxyl groups or are C₂ -C₂₀ alkylenewhich is interrupted by 1-10 --O-- or --NH--, and Z is a --COOX or --SO₃X group, and Z' is --SO₃ X,with the proviso that the compound of formulaI contains at least one group of formula --COOX or --SO₃ X; and thenapplying said aqueous solution as an ink onto a recording material forink jet printing to form an ink jet print containing an effectivestabilizing amount of said compound of formula I.
 2. A method accordingto claim 1 where in the compound of formula IR₁ is hydrogen, halogen, C₁-C₄ alkyl, C₁ -C₄ alkoxy, --COO--R₉ --OSO₃ X, --COOX or --SO₃ X, R₂ ishydrogen, C₁ -C₈ alkyl, C₇ -C₉ phenylalkyl or a --Y--Z group, R₃ ishydrogen, C₁ -C₄ alkyl, --Y--Z group or a --Y--O--Z' group, X ishydrogen or M, M is Li, Na, K, ##STR23## wherein R₄, R₅, R₆ and R₇ areeach independently of one another H, C₁ -C₄ alkyl or hydroxyethyl, Y isa direct bond or a group selected from --R₈ --, --R₈ --CONH--R₉ --,##STR24## wherein R₈ is C₁ -C₆ alkylene and R₉ and R₁₀ are eachindependently of the other C₁ -C₁₀ alkylene which may be substituted by1 or 2 hydroxyl groups or C₂ -C₂₀ alkylene which is interrupted by 1-10--O--, and Z is a --COOX or --SO₃ X group and is Z' --SO₃ X.
 3. A methodaccording to claim 2 where in the compound of formula IR₁ is hydrogen,chloro, --CO--OC₂ H₄)_(x) OSO₃ X, --Y--Z group, R₃ is hydrogen or a--Y--Z group and x is an integer from 2 to 8, and M, X, Y and Z are asdefined in claim
 2. 4. A method according to claim 3 where in thecompound of formula I, R₁, R₂ and R₃ are as defined in claim 3,X is Li,Na, K or ##STR25## Y is a direct bond or a group selected from --R₈ --,--R₈ --CONH--R₉ --, ##STR26## or --R₈ --COO--R₉ --, Z is a --COOX or--SO₃ X group, and R₄, R₅, R₆ and R₇ are each independently of oneanother H, C₁ -C₄ alkyl or hydroxyethyl, R₈ is C₁ -C₆ alkylene and R₉ isC₁ -C₁₀ alkylene which may be substituted by 1 or 2 hydroxyl groups orC₂ -C₂₀ alkylene which is interrupted by 1-10 --O--.
 5. A methodaccording to claim 1 where in the compound of formula I, R₂ is in theortho-position and R₃ is in the para-position to the OH group.
 6. Amethod according to claim 1 wherein component (ii) is 0.1 to 10% byweight based on the total solution.
 7. A method according to claim 1wherein the compound of formula I is ##STR27##
 8. A method according toclaim 1 wherein the compound of formula I is ##STR28##
 9. A methodaccording to claim 1 wherein the compound of formula I is ##STR29##